+ elsif ($config{cgi}) {
+ # Avoid more than one ikiwiki cgi running at a time by
+ # taking a cgi lock. Since ikiwiki uses several MB of
+ # memory, a pile up of processes could cause thrashing
+ # otherwise. The fd of the lock is stored in
+ # IKIWIKI_CGILOCK_FD so unlockwiki can close it.
+ $pre_exec=<<"EOF";
+ {
+ int fd=open("$config{wikistatedir}/cgilock", O_CREAT | O_RDWR, 0666);
+ if (fd != -1 && flock(fd, LOCK_EX) == 0) {
+ char *fd_s;
+ asprintf(&fd_s, "%i", fd);
+ setenv("IKIWIKI_CGILOCK_FD", fd_s, 1);
+ }
+ }
+EOF
+ }